II) 



THE ACTINOMYCETES, Vol. II 



1 



Figure 2. Schematic representation of tuft and cluster formation by certain Streptomyces species 

 (Reproduced from: Shinobu, R. Mem. Osaka Univ. Lib. Arts and Ed. B. Nat. Sci. 7, 1958). 



might have been sufficient to account for the 

 minor differences in the color of mycelium 

 or in the pigmentation of the medium. But 

 what is one to do when the original culture 

 is recorded as producing a yellow aerial my- 

 celium on a given medium, whereas the new 

 isolate gives a buff or brown mycelium? The 

 answer would be that if all the other recog- 

 nizable properties are the same or similar, 

 this would be nothing more than a variant. 

 Were one to plate out a single culture and 

 pick a large number of colonies, similar varia- 

 tions could no doubt be observed. 



Unfortunately, it has frequently been 

 found much easier lo assign undue impor- 

 tance to these variations and designate a 

 freshly isolated culture as a new species. 

 Some justification for this attitude has been 

 found in the fact that the new culture may 

 possess an important economic property, 

 such as the production of a new antibiotic. 

 1 1 is largely for this reason that within the 

 last I.") years more "new" species have been 

 created than in all the previous 7."> years 



since Ferdinand Cohn first described his 



Streptothrix. 



Requirements for Adequate Species De- 

 scriptions 



In accordance with the rules of the Inter- 

 national Code of Nomenclature of Bacteria 

 and Viruses, certain procedures must be fol- 

 lowed in describing bacterial species. These 

 are summarized b^y Ainsworth and Cowan 

 (1954) as follows: 



The name must be effectively published. 



The name must be validated by a concise de- 

 scription of the diagnostic features of the new 

 isolate. 



The etymology of the name should be ex- 

 plained. 



No Latin diagnosis is required. 



When descriptions are reported in a language 

 unfamiliar to the majority of workers, it is recom- 

 mended that the authors simultaneously publish 

 the diagnosis in a more familiar language. 



Subcultures of the type strains should be de- 

 posited at one or more of the national culture 

 collections. 



Unfortunately, these simple rules have 



